On a night of riding stars a young orphan squirrel is found abandoned on the beach. Urchin is raised on the island of Mistmantle, surrounded by the enchanted mists that protect the island from outside threats. A prophecy has been made in his name, but Urchin has no idea of this nor of what the future will bring.

The rule of the kind and fair King and Queen Brushen is threatened by plot and intrigue within their court, and a wicked pair attempt to seize control of the island, introducing a regime of culling and forced labour. Urchin soon realises that he will have a very special role to play in the dramatic battle to save Mismantle that ensues.